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Colorectal cancer screening can benefit patients through 2 mechanisms. First, a screening colonoscopy will increase the likelihood of early-stage cancer diagnosis among patients with prevalent disease (1). Because of the slow-growing nature of colorectal cancer, clinical benefits of this stage shift take years to accrue (1, 2). This is because the colorectal cancer survival benefit is due to the detection and treatment of early-stage cancer that otherwise would not have resulted in death for at least 5 years. Hence, further understanding of life expectancy after early-stage cancer diagnosis should inform decision making about screening by identifying patients who are unlikely to live long enough to receive the benefit. Second, as Dr. Burack emphasizes, colorectal cancer screening can also benefit patients by the removal of precancerous lesions and the decrease in the incidence of colorectal cancer. However, the interval between the onset of an adenoma and the clinical diagnosis of cancer has been estimated to be as long as 20 years (3).